include/asm-s390/pgalloc.h

   1 /*
   2  *  include/asm-s390/pgalloc.h
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "include/asm-i386/pgalloc.h"
  10  *    Copyright (C) 1994  Linus Torvalds
  11  */
  12
  13 #ifndef _S390_PGALLOC_H
  14 #define _S390_PGALLOC_H
  15
  16 #include <linux/threads.h>
  17 #include <linux/gfp.h>
  18 #include <linux/mm.h>
  19
  20 #define check_pgt_cache()       do {} while (0)
  21
  22 unsigned long *crst_table_alloc(struct mm_struct *, int);
  23 void crst_table_free(unsigned long *);
  24
  25 unsigned long *page_table_alloc(int);
  26 void page_table_free(unsigned long *);
  27
  28 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  29 {
  30         *s = val;
  31         n = (n / 256) - 1;
  32         asm volatile(
  33 #ifdef CONFIG_64BIT
  34                 "       mvc     8(248,%0),0(%0)\n"
  35 #else
  36                 "       mvc     4(252,%0),0(%0)\n"
  37 #endif
  38                 "0:     mvc     256(256,%0),0(%0)\n"
  39                 "       la      %0,256(%0)\n"
  40                 "       brct    %1,0b\n"
  41                 : "+a" (s), "+d" (n));
  42 }
  43
  44 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  45 {
  46         clear_table(crst, entry, sizeof(unsigned long)*2048);
  47         crst = get_shadow_table(crst);
  48         if (crst)
  49                 clear_table(crst, entry, sizeof(unsigned long)*2048);
  50 }
  51
  52 #ifndef __s390x__
  53
  54 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  55 {
  56         return _SEGMENT_ENTRY_EMPTY;
  57 }
  58
  59 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  60 #define pud_free(x)                             do { } while (0)
  61
  62 #define pmd_alloc_one(mm,address)               ({ BUG(); ((pmd_t *)2); })
  63 #define pmd_free(x)                             do { } while (0)
  64
  65 #define pgd_populate(mm, pgd, pud)              BUG()
  66 #define pgd_populate_kernel(mm, pgd, pud)       BUG()
  67
  68 #define pud_populate(mm, pud, pmd)              BUG()
  69 #define pud_populate_kernel(mm, pud, pmd)       BUG()
  70
  71 #else /* __s390x__ */
  72
  73 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  74 {
  75         return _REGION3_ENTRY_EMPTY;
  76 }
  77
  78 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  79 #define pud_free(x)                             do { } while (0)
  80
  81 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  82 {
  83         unsigned long *crst = crst_table_alloc(mm, s390_noexec);
  84         if (crst)
  85                 crst_table_init(crst, _SEGMENT_ENTRY_EMPTY);
  86         return (pmd_t *) crst;
  87 }
  88 #define pmd_free(pmd) crst_table_free((unsigned long *) pmd)
  89
  90 #define pgd_populate(mm, pgd, pud)              BUG()
  91 #define pgd_populate_kernel(mm, pgd, pud)       BUG()
  92
  93 static inline void pud_populate_kernel(struct mm_struct *mm,
  94                                        pud_t *pud, pmd_t *pmd)
  95 {
  96         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
  97 }
  98
  99 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 100 {
 101         pud_t *shadow_pud = get_shadow_table(pud);
 102         pmd_t *shadow_pmd = get_shadow_table(pmd);
 103
 104         if (shadow_pud && shadow_pmd)
 105                 pud_populate_kernel(mm, shadow_pud, shadow_pmd);
 106         pud_populate_kernel(mm, pud, pmd);
 107 }
 108
 109 #endif /* __s390x__ */
 110
 111 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 112 {
 113         unsigned long *crst = crst_table_alloc(mm, s390_noexec);
 114         if (crst)
 115                 crst_table_init(crst, pgd_entry_type(mm));
 116         return (pgd_t *) crst;
 117 }
 118 #define pgd_free(pgd) crst_table_free((unsigned long *) pgd)
 119
 120 static inline void
 121 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
 122 {
 123 #ifndef __s390x__
 124         pmd_val(pmd[0]) = _SEGMENT_ENTRY + __pa(pte);
 125         pmd_val(pmd[1]) = _SEGMENT_ENTRY + __pa(pte+256);
 126         pmd_val(pmd[2]) = _SEGMENT_ENTRY + __pa(pte+512);
 127         pmd_val(pmd[3]) = _SEGMENT_ENTRY + __pa(pte+768);
 128 #else /* __s390x__ */
 129         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 130         pmd_val1(*pmd) = _SEGMENT_ENTRY + __pa(pte+256);
 131 #endif /* __s390x__ */
 132 }
 133
 134 static inline void
 135 pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *page)
 136 {
 137         pte_t *pte = (pte_t *)page_to_phys(page);
 138         pmd_t *shadow_pmd = get_shadow_table(pmd);
 139         pte_t *shadow_pte = get_shadow_pte(pte);
 140
 141         pmd_populate_kernel(mm, pmd, pte);
 142         if (shadow_pmd && shadow_pte)
 143                 pmd_populate_kernel(mm, shadow_pmd, shadow_pte);
 144 }
 145
 146 /*
 147  * page table entry allocation/free routines.
 148  */
 149 #define pte_alloc_one_kernel(mm, vmaddr) \
 150         ((pte_t *) page_table_alloc(s390_noexec))
 151 #define pte_alloc_one(mm, vmaddr) \
 152         virt_to_page(page_table_alloc(s390_noexec))
 153
 154 #define pte_free_kernel(pte) \
 155         page_table_free((unsigned long *) pte)
 156 #define pte_free(pte) \
 157         page_table_free((unsigned long *) page_to_phys((struct page *) pte))
 158
 159 #endif /* _S390_PGALLOC_H */